(mean) apr_1965_nb
(mean) apr_1965_avg
(mean) oct_1967_nb
(mean) oct_1967_avg
(mean) apr_1968_nb
(mean) apr_1968_avg
(mean) jun_1963_nb
(mean) jun_1963_avg
(mean) jun_1966_nb
(mean) jun_1966_avg
(mean) apr_1967_nb
(mean) apr_1967_avg
(mean) oct_1966_nb
(mean) oct_1966_avg